41 lines
1.6 KiB
Text
41 lines
1.6 KiB
Text
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\--- Day 3: Squares With Three Sides ---
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----------
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Now that you can think clearly, you move deeper into the labyrinth of hallways and office furniture that makes up this part of Easter Bunny HQ. This must be a graphic design department; the walls are covered in specifications for triangles.
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Or are they?
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The design document gives the side lengths of each triangle it describes, but... `5 10 25`? Some of these aren't triangles. You can't help but mark the impossible ones.
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In a valid triangle, the sum of any two sides must be larger than the remaining side. For example, the "triangle" given above is impossible, because `5 + 10` is not larger than `25`.
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In your puzzle input, *how many* of the listed triangles are *possible*?
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Your puzzle answer was `1050`.
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\--- Part Two ---
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----------
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Now that you've helpfully marked up their design documents, it occurs to you that triangles are specified in groups of three *vertically*. Each set of three numbers in a column specifies a triangle. Rows are unrelated.
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For example, given the following specification, numbers with the same hundreds digit would be part of the same triangle:
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```
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101 301 501
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102 302 502
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103 303 503
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201 401 601
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202 402 602
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203 403 603
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```
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In your puzzle input, and instead reading by columns, *how many* of the listed triangles are *possible*?
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Your puzzle answer was `1921`.
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Both parts of this puzzle are complete! They provide two gold stars: \*\*
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At this point, all that is left is for you to [admire your Advent calendar](/2016).
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If you still want to see it, you can [get your puzzle input](3/input).
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